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Abstract:

The present invention relates to compositions that can improve biological
activity or can increase population density of natural or beneficial
microorganisms on surfaces. By proper use of the compositions, the
present invention provides uses of protecting plants from plant pathogen,
harmful insects or weedy plants or of promoting plant growth. By proper
use of the compositions in the present invention, biological activity or
population density of natural or beneficial microorganisms can be
increased and the improved biological activity or population density of
the microorganisms can protect plants from harmful organisms including
plant pathogens, harmful insects or weedy plants or can promote plant
growth.

Claims:

1. A composition comprising SAP (super absorbent polymer) to improve
biological activity or to increase microbial population of microorganisms
that exist on surfaces.

2. The composition according to claim 1, characterized in that it
additionally comprises at least one microbial nutrient that can be
utilized by the microorganisms.

3. The composition according to claim 1, characterized in that it
additionally comprises at least one beneficial microorganism that can
inhibit growth of plant pathogens, harmful insects or weedy plants or can
promote plant growth.

4. The composition according to claim 1, characterized in that it
additionally comprises at least one beneficial microorganism that can
inhibit growth of harmful animals.

5. The composition according to claim 1, characterized in that it
additionally comprises at least one surfactant to improve spreadability
of the composition on surfaces.

6. The composition according to claim 1, characterized in that it
additionally comprises at least one single or complex mineral salt to
improve wettability of the composition in water.

7. The composition according to claim 1, characterized in that said SAP is
SAP made from starch.

8. The composition according to claim 1, characterized in that the content
of SAP is the range of 20% to 95% by weight of the composition.

9. The composition according to claim 1, characterized in that the content
of SAP is the range of 0.02% to 1.0% by weight per water volume when the
composition is diluted with water.

10. The compositions according to claim 1, characterized in that said
surface is selected from plant surfaces such as leaf, stem, branch or
fruit surface, soil surfaces or animal skin surfaces.

11. The composition according to claim 2, characterized in that said
microbial nutrients are composed of PLNT media that includes potato
dextrose broth, Luria broth base, nutrient broth and tryptic soy broth
each in the amount of 25% by weight based on their standard use amount.

12. The composition according to claim 3, characterized in that said
plants are selected from the group consisting of cucumber, pepper,
potato, rice, tomato, barley, wheat, pear and rose.

13. The composition according to claim 3, characterized in that said
beneficial microorganisms are selected from the group consisting of genus
Bacillus, genus Paenibacillus, genus Streptomyces, genus Trichoderma,
genus Ampelomyces and genus Acremonium.

14. The composition according to claim 3, characterized in that said plant
pathogens are selected from the group consisting of Magnaporthe grisea,
Thanatephorus cucumeris, Phytophthora capsici, Botrytis cinerea, Puccinia
graminis, Blumeria graminis (=Erysiphe graminis) and Sphaerotheca fusca.

15. The composition according to claim 3, characterized in that said
harmful insects are selected from genus Plutella.

16. The composition according to claim 3, characterized in that said weedy
plants are selected from plants that grow at time and place that plant
growers do not desire.

17. The composition according to claim 4, characterized in that said
harmful animals are selected from the group consisting of cockroach, ants
and snails.

18. Use of the composition according to claim 1 on plant surfaces
including leaf, stem, branch, flower or fruit, or soil surfaces on which
lawn grasses grow.

19. Use of the composition according to claim 1 to inhibit harmful
organisms on surfaces or to promote plant growth.

Description:

TECHNICAL FIELD

[0001]The present invention relates to compositions to increase biological
activity or population density of microorganisms on surface. Compositions
of the present invention can be used to protect plants from harmful
organisms such as plant pathogens, insects or weedy plants, or to promote
plant growth.

BACKGROUND ART

[0002]There are various natural microorganisms living on plant surfaces
including leaf, stem, branch, flower or fruit, on soil surface of lawn,
or surfaces of an animal such as cockroaches, snails or ants (hereafter
referred as "surfaces"). These microorganisms exist together with
saprophytic, symbiotic or parasitic interactions. On plant surfaces,
parasitic plant pathogens cause plant diseases usually by increasing
their populations under favorable environmental conditions, and harmful
insects also increase their population resulting in damages to plants.
Weed plants also results in reduced growth of cultivating crops or plants
due to competition among plants for nutrition or space. The plant
pathogens, harmful insects and weeds (hereafter referred as "harmful
organisms") have been threats of human efforts to secure stable
production of foods for mankind. Currently, humans mainly rely on use of
chemical pesticides to protect plants from these harmful organisms. Up to
now, chemical pesticides have been used as the most effective means for
protecting crops from plant pathogens, insects and weeds. Current market
size is approximately 30 US billion dollars in the world and 1 US billion
dollars in Korea. However, chemical pesticides are known with many
adverse problems of causing ecological disorders by suppressing not only
harmful organisms but also other natural beneficial organisms as an
adverse side effect. Residues or metabolites of chemical pesticides may
also have a toxic effect to producers of chemical pesticides, farmers or
consumers. In addition, repeated use of chemical pesticides may induce
resistance to plant pathogens, insects or weeds, resulting in their
reduced sensitivity to chemical pesticides. Sometimes, leakage of
chemical pesticides may cause air, water or soil contamination of our
environment.

[0003]Human efforts have been keeping to supplement or to replace chemical
pesticides that have potential risks as described above. One alternative
is use of certain microorganisms to manage harmful organisms. These
microorganisms (hereafter referred as "plant protection microorganisms")
have their biological activity to inhibit certain harmful organisms under
favorable environment conditions for their growth. This microbial method
has been socially needed mainly due to its safety profile to mammals and
environments in comparison to chemical pesticides. Recently, many
countries including the United States, European countries, Japan and
Korea have launched regulations to encourage research, development and
registration of industrial products of "plant protection microorganisms"
to manage "harmful organisms". "Plant protection microorganisms" are
developed usually by being isolated from nature, artificially cultivated
in their own media and formulated before use. However, this microbial
method also has technical limitations and has not been successful in
industrial viewpoints compared to chemical pesticides due to the
technical limitations, although it is known to be safe to humans and
environment. The microbial method is usually not sufficient to protect
plants from "harmful organisms" or highly variable in its efficacy that
highly depends on environmental conditions. Another limitation is
relatively higher cost of microbial products, compared to chemical
pesticides. "Plant protection microorganisms" usually require stricter
conditions for their survival or biological activity during
manufacturing, transportation, storage or after application by farmers in
fields, and requirement of these strict conditions often results in
higher costs than chemical pesticides. Especially, unstable or unreliable
efficacy depending on environmental conditions often requires growers of
taking economic risks from damages by "harmful organisms". These problems
are considered main reasons why microbial method has not been adopted
widely in industry, although it is generally known to be safe to humans
and environment.

[0004]People have been using chemical fertilizers for long time to enhance
agricultural productivity. However, repeated use of chemical fertilizers
has caused reduced productivity of agricultural land by salt accumulation
in soils and other negative problems such as water pollution. In order to
overcome these problems, people have been trying to recover productivity
of agricultural land by using natural organic materials instead of
chemical fertilizers. Natural organic materials are known to exhibit
fertilizer effect by their metabolites including small organic molecules
and minerals. These organic materials are mainly degraded by natural
microorganisms. These microorganisms (hereafter referred as "plant growth
promotion microorganisms") exist in nature in a great amount, and proper
use of these microorganisms can replace or supplement chemical
fertilizers. However, "plant growth promotion microorganisms" have
similar technical limitations as in the microbial method with "plant
protection microorganisms" such as lower efficacy, unstable or unreliable
efficacy by being sensitive to environment conditions, higher price than
chemical fertilizers. These technical limitations also lead to limited
use of microbial method in industrial applications.

[0005]The above-described unstable or insufficient effect of the methods
based on "plant protection microorganisms" and "plant growth promotion
microorganisms" (hereafter referred as "beneficial microorganism") is
caused by the fact that biological activities of plant protection or
growth promotion on plant surfaces often largely depends on environmental
conditions for their survival. More specifically, biological activities
of microorganisms on plant surface are known to be affected by factors
such as moisture, temperature, UV light, nutrients and so on (Steven E.
Lindow and Maria T. Brandl. 2003. Microbiology of the phyllosphere.
Applied and Environmental Microbiology 69:1875-1883). Beneficial
microorganisms applied to plant surface for plant protection or plant
growth promotion are also generally affected for their survival or
biological activities by these environmental factors. Especially, under
environment conditions that cause dryness of plant leaf and then reduced
availability of nutrients in leaf or that expose plant leaves direct to
sunlight, population of these beneficial organisms significantly
decreases or their biological activities are lowered.

[0006]The present invention was focused on developing compositions for
strengthening availability of water and microbial nutrients on plant
surfaces, and therefore resulting in increased population or biological
activities of microorganisms on surfaces. Water on plant surfaces is
provided by natural precipitation or artificial irrigation, and water
amount is fluctuating on plant surfaces in terms of time and space.
Generally microorganisms are more sensitive to water for their biological
activities than plants. More specifically, water on plant surface is
dropped off leaves down to ground surface by gravity or vanished from
plant surfaces by evaporation. And water remaining on plant surfaces is
also variably distributed by surface structures on leaves. For example,
water remaining on plant surfaces is mainly found along leaf veins or
around trichomes, and results in uneven distribution of water that leads
limited availability of water to microorganisms living on leaves. This
may be one of reasons why microorganisms are found along leaf veins or
around trichomes. Limited water availability for microorganisms
(hereafter referred as "available water") on plant surfaces generally
leads to reduced microbial population or reduced biological activity and
transformation into resting structures like spores. Therefore, "available
water" is considered highly important to increase or maintain microbial
populations or their biological activities. Furthermore, "available
water" is also important for availability of microbial nutrients on
surfaces to be accessible to microorganisms on plant surfaces.
Microorganisms usually do not have means for active movement on plant
surfaces and thus tend to get moved passively by water stream existing on
plant surfaces. Therefore, limited water availability also means limited
availability of microbial nutrients that are dissolved or suspended in
water. As such, "available water" also plays a role to deliver microbial
nutrients to microorganisms on plant surfaces.

[0007]Among microbial nutrients, carbon and nitrogen sources are utmost
important for microorganisms to maintain their population or to express
their biological activities. Generally, within a certain space and time
point, various natural microorganisms exist on plant surface in a great
amount. This coexistence of various microorganisms results in high
competition among microorganisms for microbial nutrients (Steven E.
Lindow and Maria T. Brandl. 2003. Microbiology of the phyllosphere.
Applied and Environmental Microbiology. Vol 69:1875-1883). Especially,
"beneficial microorganisms" that are introduced artificially by human for
plant protection or plant growth promotion are usually positioned
unfavorable for their survival or biological activities on plant surfaces
that are already occupied by natural microorganisms with superior
ecological fitness. Most "beneficial microorganisms" are grown
artificially in culture media to optimize their maximum growth in
population and then introduced to natural field conditions. Because of
this reason, these "beneficial microorganisms" cannot be considered
positioned competitive in natural ecological conditions. In addition,
these "beneficial microorganisms" are generally manufactured in their
resting structures like spores that are biologically less active than
their vegetative structures. These manufacturing processes of growing
them in artificial culture media and storing in resting structures can be
the reasons of low competitiveness of "beneficial microorganisms" on
plant surfaces compared to natural microorganism that are ecologically
already fit for their survival.

[0008]Natural microorganisms that live on plant surfaces compete with
plant pathogenic microorganisms for water, microbial nutrients or space,
and this competition may result in reduced plant disease development.
Therefore, increased competition between natural saprophytic
microorganisms and plant pathogenic microorganisms can be considered
desirable in terms of plant protection from plant pathogens. Moreover, in
order to protect certain plants from certain plant pathogens, use of
certain microorganisms that are selected for the competition,
artificially cultured on media and to have increased population can be
more desirable than simple increase of natural saprophytic
microorganisms. On the other hand, plant protections from harmful insects
or weedy plants by using natural microorganisms are fairly difficult
because their population density or biological activity is not high
enough to inhibit harmful insects or to suppress weedy plants. In this
case, beneficial microorganisms that are artificially grown in culture
media are more desirable. Therefore, certain beneficial microorganisms
that specifically inhibit certain harmful insects or specifically inhibit
certain weeds are needed to be artificially introduced to plant surfaces.
For promotion of plant growth by using beneficial microorganisms,
artificial introduction is desirable than use of natural saprophytes.

[0009]It has not been technically well established to provide microbial
nutrients that can be used selectively by beneficial microorganisms but
not by natural microorganism population. In nature, microorganisms on
plant surfaces keep dynamically changing their species and numbers in
given times and spaces. On plant surfaces, it is known that many
different microorganisms exist together simultaneously. For example, 37
genera and 85 species of microorganisms are reported in phyllosphere of
oat, olive, sugarcane and wheat (Ching-Hong Yang, David E. Crowley, James
Borneman and Noel T. Keen. 2001. Microbial phyllosphere populations are
more complex than previously realized. PNAS. Vol. 98:3889-3894). Such
diversity of microorganisms may be similarly applied to other plants.
Therefore, when beneficial microorganisms are artificially introduced on
plant surfaces, they have to compete with other natural microorganisms
within the same space under various environmental conditions. This
dynamic competition makes beneficial microorganisms difficult to occupy a
dominant position in given spaces for long time. One method to overcome
this limitation can be use of microbial nutrients that are selectively
used by certain beneficial microorganisms. For example, certain
beneficial microorganisms can use oils as their carbon sources, whereas
most natural microorganisms cannot use oils as nutrients. Another method
is use of antimicrobial agents that are not inhibitory to one or some of
beneficial microorganisms but inhibitory to most natural microorganisms.
With this method, beneficial microorganisms can establish their
population securely in their early application stage while natural
microorganisms are selectively controlled. If needed, beneficial
microorganisms can be induced to be resistant to certain antimicrobial
agents in the laboratory and may be used for this purpose. Some chemical
bactericides or fungicides can be used as the antimicrobial agents.
However, even in this case, these antimicrobial agents are used at much
lower application rates, due to the different purpose of their use and
low use concentration.

[0010]A key concept of the present invention is to use super absorbent
polymer (hereafter referred as "SAP") to increase population density or
biological activity of microorganisms on plant surfaces. SAP in the
present invention is defined as all polymers that have hydrophilic
function and that can hold tap water at least for several ten times of
their own weight for a certain period of time. SAP was introduced by USDA
in 1970s and industrially used since 1980s. Their main applications are
for sanitation purposes including disposable diapers and hygienic bands
for women. In agriculture and forestry, SAP also has been used in soil to
provide plant roots with water for longer time in arid area or to
increase aeration in soil (Sang-Bum Park. 1994. Characteristics of Super
Absorbent Polymer and State of the Art. Mokchae Konghak 22(1): 91-112).
Although SAP can be classified into natural and synthetic SAP based on
source of its raw skeleton materials, it was obtained by crosslinking
soluble raw polymer materials into non-soluble forms, which consequently
can hold water several ten times of water of its own weight in a gel
form. (Sang-Bum Park. 1994. Characteristics of Super Absorbent Polymer
and State of the Art. Mokchae Konghak 22(1):91-112).

[0011]U.S. Pat. No. 9,009,020 describes manufacturing process of SAP for
agricultural application. It is disclosed in this patent that SAP can be
used in soil, on seed or root to improve aeration in soil, to improve
germination and emergence of seeds, to improve plant growth and yield,
and to reduce cost of water irrigation. For this purpose, inventors
describe convenient use by manufacturing SAP having the size in range of
5-24 meshes. Korean Patent Application Laid-Open No. 2002-0002852
describes use of SAP on seeds pelleted with ectomycorrhizae to increase
storage period, help germinated root to come out of epidermis of pelleted
seeds and to reduce water stress of plant seedlings. Another research was
conducted in Korea using 2% SAP of soil by weight in potting soil to
improve suppression activity of Serratia plymutica A21-4 that is
effective against soil born plant disease. By this application, emergence
and growth promotion of red-pepper seedlings were reported to be
significantly enhanced (Shun-Shan Shen, Won-il Kim and Chang-Seuk Park.
2006). Effect of hydrogel on survival of Serratia plymuthica A21-4 in
soils and plant disease suppression. Plant Pathology Journal Vol.
22:364-368). In addition, population density of Serratia plymutica A21-4
was reported to be significantly increased on roots and rhizosphere
whereas population density of Phytophthora capsici, a causal pathogen of
red-pepper blight, was reduced.

[0012]However, all of these reports are directed to the use of SAP in soil
that is working under soil surface. There has been no report about the
use of SAP that is applied on plant surfaces to increase population
density or biological activities of natural or beneficial microorganisms.
In addition, there has been no report of using SAP to protect plants from
harmful microorganisms or to promote plant growth by increasing
population density or biological activities of microorganisms on plant
surfaces.

DETAILED DESCRIPTION OF THE INVENTION

Technical Problem

[0013]The present invention was based on an idea of protecting plants from
harmful organisms or promoting plant growth by increasing population
densities or biological activity of saprophytic or beneficial
microorganisms on plant, soil and organism surfaces, in combination with
SAP to increase water availability needed for microorganisms on surfaces.
Therefore, the present invention provides compositions containing SAP
(hereafter referred as "SAP composition") which can be used for
increasing population densities or biological activity of microorganisms
on surface, and can be used to protect plants from harmful organisms, to
promote plant growth or others.

[0015]SAP compositions of the present invention may provide additional
water or microbial nutrients needed for natural or beneficial
microorganisms living on surfaces of plants, soil and animals. This
additional water or microbial nutrients may increase microbial population
on surfaces and improve biological activity of the microorganisms. More
specifically, the SAP compositions of the present invention provide
additional water or microbial nutrients that extend supplying time of
water or microbial nutrients to increase microbial population on
surfaces. SAP compositions added with microbial nutrients are more
effective to increase microbial populations on surfaces. The SAP
compositions of the present invention, which comprise SAP, microbial
nutrients and specific beneficial microorganisms, are prepared to
increase the population of artificially-introduced beneficial
microorganisms rather than natural saprophytic beneficial microorganisms.
When the SAP compositions comprise beneficial microorganisms that are
inhibitory to growth of natural saprophytic microorganisms, these SAP
compositions may inhibit natural microorganisms, thus resulting in
reduction of population density of the natural microorganisms. In
addition, by adding some specific beneficial microorganisms that are
selectively growing on specific microbial nutrients or that are resistant
to certain specific antimicrobial agents in the SAP compositions, the SAP
composition of the present invention can be used to increase specific
beneficial microorganisms rather than natural saprophytic beneficial
microorganisms.

[0016]In summary, the SAP compositions of the present invention provide
may be used to increase natural saprophytic or added beneficial
microorganisms, to reduce population density of natural microorganisms by
inhibitory activity of secondary metabolites produced by added beneficial
microorganisms or by antimicrobial agents that are selectively added in
the SAP compositions. Natural saprophytic or added beneficial
microorganisms that are increased in population by using the SAP
composition of the present invention may compete more effectively with
plant pathogenic microorganisms for microbial nutrients and spaces that
result in reduced disease development. When the SAP compositions added
with certain microorganisms that have insecticidal activity, the
insecticidal microorganisms may have higher chance of suppressing harmful
insects on surfaces when applied properly to plant surfaces. When the SAP
compositions added with herbicidal microorganisms, the herbicidal
microorganisms may have higher chances of suppressing weedy plants in
selective ways when applied properly to surfaces of weedy plants. When
the SAP compositions added with specific beneficial microorganisms that
are inhibitory to growth of snails, cockroaches or ants, the beneficial
microorganisms may also have higher chances of suppressing or eliminating
harmful animals when applied properly to animal surfaces.

BEST MODE FOR CARRYING OUT THE INVENTION

[0017]To achieve the above-described purpose of the invention, the present
invention provides compositions comprising SAP to increase microbial
population or biological activities of beneficial microorganisms on
plant, soil or animal surfaces of plant, soil and animal.

[0018]The SAP composition of the present invention additionally may
contain at least one nutrient that can be used by natural saprophytic or
added beneficial microorganisms.

[0019]The SAP composition of the present invention additionally may
contain at least one beneficial microorganism that can inhibit plant
pathogens, harmful insects or weedy plants or that can promote plant
growth.

[0020]The SAP composition of the present invention additionally may
contain at least one beneficial microorganism that can inhibit harmful
animals.

[0021]The SAP composition of the present invention additionally may
contain at least one surfactant to achieve even spreading of the
composition on surfaces.

[0022]The SAP composition of the present invention additionally may
contain at least one single or multiple mineral salt to improve
wettability of the composition in water.

[0023]The SAP composition of the present invention is characterized in
that SAP is starch-based SAP.

[0024]The SAP composition of the present invention is characterized in
that the SAP content ranges from 20% to 95% by weight.

[0025]The SAP composition of the present invention is characterized in
that the SAP content ranges from 0.02% to 1.0% by weight in a given water
volume, when the composition is diluted with water.

[0026]The SAP composition of the present invention is characterized in
that the surfaces are surfaces of plant leaves, stems, branches, flowers
or fruits, surfaces of ground soil, or surfaces of animals.

[0027]The SAP composition of the present invention is characterized in
that the microbial nutrient is PLNT powder of culture broth that consists
of potato dextrose broth, Luria broth base, nutrient broth and tryptic
soy broth each comprised in an equal amount by weight.

[0028]The SAP composition of the present invention is characterized in
that the plants are selected from cucumber, red pepper, potato, rice,
tomato, barley, wheat, pear or rose.

[0029]The SAP composition of the present invention is characterized in
that the beneficial microorganisms are selected from bacterial genera of
Bacillus, Paenibacillus or Streptomyces, fungal genera of Trichoderma,
Ampelomyces or Acremonium.

[0031]The SAP composition of the present invention is characterized in
that the harmful insect is genus Plutella.

[0032]The SAP composition of the present invention is characterized in
that the weedy plants are the plants that are growing in field in a given
time and space that are not intended by plant growers.

[0033]The SAP composition of the present invention is characterized in
that the harmful animals are cockroaches, ants or snails.

[0034]The present invention provides use of the SAP compositions on plant
surfaces or soil surfaces.

[0035]The present invention provides use of the SAP compositions to
suppress harmful organisms on surfaces or to promote plant growth.

[0036]Hereafter, more specific descriptions of the present invention are
given.

[0037]The present invention is about compositions of increasing biological
activities or population density of natural saprophytic or added
beneficial microorganisms on surfaces and their uses. The compositions of
the present invention comprise SAP that is super absorbent polymer of
water. Depending on application and necessity, the compositions of the
present invention may contain microbial nutrients or beneficial
microorganisms. Furthermore, wetting agents or surfactants may be added
to improve wettability in water and spreadability on surfaces,
respectively. In the present invention, a key material used to increase
water amount and to extend supply time of water available for
microorganisms are super absorbent polymer (hereafter referred as "SAP").
Microbial nutrients were composed of culture broth that is widely used by
microbiologists in laboratory for research. Beneficial microorganisms
were obtained from a commercial provider or obtained from researchers who
study the corresponding microorganisms. In the compositions of the
present invention, mineral salts and surfactants are selected and
properly used to improve wettability in water, and spreadability of the
composition on surfaces, respectively.

1. SAP (Super Absorbent Polymer)

[0038]The SAP used mainly in the present invention is starch-based,
specifically Zeba (product brand name), comprising a major component
starch-g-poly(2-propenamide-co-2-propenoic acid) potassium salt (CAS
Registry No. 107830-79-5) that is manufactured by Absorbent Technologies,
Inc. The SAP content was 50% of the compositions by weight prior to
dilution in water, and 0.02%-1.0% by weight in a given water volume when
diluted in water. The SAP content in said SAP compositions and examples,
the SAP content was 0.5% by weight in a given water volume. For
comparison purpose, an acrylamide-based SAP (GS-3000), manufactured by
Kolon Industries Inc., was used instead of Zeba, which resulted in
similar effects of increasing microbial population when tested on
cucumber leaves. In the present invention, SAP was milled into fine
powders to have a diameter the same or less than 0.1 mm. Smaller the SAP
particles, better the SAP suspension after dilution spreads over wide
range of plant surfaces. However, the above-described kinds, contents and
diameters of SAP were given to exemplify the present invention and does
not restrict kinds and a method of preparing SAP that are comprised in
compositions of the present invention.

2. Microbial Nutrients

[0039]In the present invention, a microbial nutrient, named as PLNT powder
medium, was used. The PLNT powder medium consists of potato dextrose
broth, Luria broth base, nutrient broth and tryptic soy broth that are
all manufactured by Difco Laboratories, USA. One quarter of recommended
use of each medium was combined to prepare the PLNT powder medium. Good
growth of various microorganisms was confirmed on PLNT agar medium. The
PLNT powder medium was used with 5% by weight in the composition of the
present invention. However, the PLNT powder broth was used as an example
of the present invention and kinds or contents of microbial nutrients are
not limited thereto. Rather, other microbial nutrients that provide
carbon, nitrogen, amino acids, minerals or vitamins required for
microbial growth can be also used.

3. Beneficial Microorganisms

[0040]All beneficial microorganisms used in the present invention were
obtained from a commercial provider or from researchers. Beneficial
microorganisms used for plant protection from plant pathogens belong to
bacterial genera of Bacillus, Paenibacillus or Streptomyces or fungal
genera of Trichoderma, Ampelomyces or Acremonium. Beneficial
microorganism used for plant protection from harmful insect belongs to
bacterial genus of Bacillus thuringiensis, and that used for plant
protection from weedy plant belongs to bacterial genus of Botrytis
cinerea. Beneficial microorganism used for growth promotion of plants
belongs to bacterial genus of Bacillus vallismortis. References of each
beneficial microorganism are given below.

[0060]In the present invention, for experimental purpose, microorganisms
obtained from one liter of water shaken vigorously in a 250 ml of
Erlenmeyer flask with 100 g of fresh cucumber leaves sampled from adult
cucumber plants, left statically for 30 minutes, shaken vigorously again,
and then filtered through two layers of sterile cheese cloths (hereafter
referred as "leaf wash water") were used as natural microorganisms. In
the present invention, plant pathogens were artificially cultured. For
plant pathogens that are not culturable due to their intrinsic obligate
parasitism, inoculum was obtained from plants which are infected with the
pathogen and show typical symptom of the infection. In the present
invention, larva of Plutella species was used as a harmful insect. In
principle, most bacteria or fungi listed on "The manual of biocontrol
agent" published by BCPC in 2004 can be considered as beneficial
microorganisms. In the manual, beneficial microorganisms that are
established on plant surface or soil surface in advance to arrival of
plant pathogens compete with plant pathogens for nutrition or space that
results in plant protection. In case of plant protection from harmful
insects, beneficial microorganisms are taken into inside harmful insects
and results in death or inactivation of harmful insects. In case of plant
protection from weedy plants, beneficial microorganisms cause diseases
that are pathogenic specifically only to the weedy plants. Therefore, the
experiments in the present invention are only to illustrate the present
invention and do not limit kinds of beneficial microorganisms or harmful
organisms.

4. Preparation of Microbial Compositions

[0061]Microbial compositions in the present invention was prepared by
milling and mixing of each component as powder with particle size that is
the same or less than 0.1 mm in average. Among the components of the
present invention, SAP was the starch-based SAP. Microbial nutrient was
the PLNT. Beneficial microorganisms were obtained from a commercial
provider or obtained, isolated for pure culture in laboratory, cultured
and prepared as powder by a freeze-drying technique. In addition, 5% of
surfactant in powder was used to accomplish even spreading of the
composition on plant surface. In the present invention, the surfactant
was softanol (CAS Registry No. 68131-40-8) manufactured by Ineos Oxide
Ltd., UK. Sofanol was adsorbed to white carbon supplied by Jungwoo
Chemical, Korea, with 1:1 ratio by weight. More specifically, softanol is
a non-ionic surfactant obtained by adding ethylene oxide to linear
secondary alcohol with 12-14 alkyl carbons. Complex mineral salts were
used in the microbial composition to improve wettability of the
composition in water. Mirigun powder, manufactured by Daeyoo, Korea, was
added as a wetting agent with 30% ratio by weight to microbial
compositions. Mirigun is a fertilizer to provide minerals required for
plant growth. In the present invention, Mirigun was used as carrier and
to improve wettability in water based on its high solubility in water and
high specific gravity. A single mineral salt such as calcium chloride can
be also applied to microbial compositions in the present invention. For
compositions without containing beneficial microorganisms, Mirigun powder
was used with 40% ratio by weight. Content of each component in 100 g
composition was described in Table 1.

[0062]These compositions are only examples and do not limit kinds of SAP,
beneficial microorganisms, microbial nutrients, surfactants or carriers
that can be used for the compositions of the present invention.

[0063]The present invention will now be described in greater detail with
reference to the following examples. However, it is only to specifically
exemplify the present invention and in no case the scope of the present
invention is limited by these examples.

Example 1

Dynamics of Microbial Populations

[0064]In this Example, effect of each composition on population density of
natural or added beneficial microorganisms present on plant surface was
monitored with time. For experimental purpose, natural microorganisms
were defined as microorganisms obtained from one liter of water shaken
vigorously in a 250 ml of Erlenmeyer flask with 100 g of fresh cucumber
leaves sampled from adult cucumber plants, maintained undisturbed for 30
minutes, shaken vigorously again, and then filtered through two layers of
sterile cheese cloths (hereafter referred as "leaf wash water"). When
cultured on LB agar medium, approximately 2×105 cfu/ml (=5.3
log cfu/ml) of natural microorganisms were detected. Of these, bacteria
were present in a dominant amount of 90% of the total population. Each
composition from the present invention at 0.5% by weight was added to the
leaf wash water to become 10 ml in total volume. Seven discs of cucumber
leaf in 3 cm diameter were soaked for 30 min and placed on a Petri dish
at room temperature. In addition, for comparison purpose, each beneficial
microorganism was added to 10 ml of the leaf wash water at the same rate
and prepared as above. Composition without microbial nutrient or
beneficial microorganism was also prepared for comparison purpose. Each
preparation was incubated for 0, 1, 2, 3, 5 and 7 day after treatment on
LB agar media at room temperature. Microbial population was properly
counted 3-7 days after incubation by dilution plating method. Beneficial
microorganisms were differentiated by their unique colony form on the
media, and all the others were considered as natural microorganisms.
These results are summarized in Table 2.

[0065]As shown in Table 2, most of the beneficial or natural
microorganisms were increased in their population when properly used with
the compositions of the present invention. Population density of natural
microorganism was increased up to 100-fold at certain time point for some
compositions. However, in case with composition 3 containing beneficial
microorganism 1 and composition 4 containing beneficial microorganism 2,
the density of the natural microorganisms was decreased or their increase
rate was reduced. This observation may be explained by antibiosis of the
beneficial microorganisms 3 and 4 that have antimicrobial activity by
producing secondary metabolites. For example, Paenibacillus elgii SD17
was reported with its broad antimicrobial activity (Kim, D. S., Bae, C.
Y., Kim, D. H, Chun, S. J., Choi, S. W., and Choi, K. H. 2005.
Paenibacillus elgii SD17 as a biocontrol agent against soil-borne turf
diseases. Plant Pathology Journal 21:328-333). Based on results in Table
1, it was found that compositions of the present invention provides more
water and microbial nutrients to microbial population on cucumber leaf
and results in increased population density of natural or beneficial
microorganisms. In addition, in case with beneficial microorganisms with
antimicrobial activity, the beneficial microorganisms were well
established by decreased population density of natural microorganisms or
by reduced increase of population density of natural microorganisms in
accordance with the application of the composition of the present
invention.

[0066]In this Example, compositions of the present invention were tested
in growth chamber for their plant protection activity against plant
pathogens; Magnaporthe grisea, Thanatephorus cucumeris, Phytophthora
capsici, Botrytis cinerea, Puccinia graminis and Blumeria graminis (i.e.,
Erysiphe graminis). The experiments were conducted on basis of general
screening methods of chemical fungicides (Choi, G. J, Kim, J.-C., Lee,
S.-W., Jang, K. S., Kim, J.-S., and Cho, K. Y. 2002. Antifungal
activities of several plant extracts against wheat leaf rust. The Korean
Journal of Pesticide Science 6(2): 87-95. In Korean). One main difference
was that each plant pathogen was inoculated 3 days after treatment of the
plant with each composition with 200-fold dilution by spraying on plant
surfaces. Treated plants were maintained by general practice, and plant
protection activity was estimated by control value. Control value (CV) is
estimated by the following formula; CV(%)={1-(diseased area ratio of
treatment group/diseased area ratio of non-treatment group)}×100.

[0067]In Table 3, SAP compositions of the present invention in general
showed protection activity against the plant diseases that resulted in
increased control value. More specifically, overall increase in control
value by the composition 1 was observed for all the diseases. Overall
increase of control value by the composition 2 was also observed for all
the diseases. The composition 2 resulted in somewhat higher control
values than the composition 1. Overall increase of control value was also
observed with the composition 3 to composition 11. Especially, control
value was improved for the compositions that showed protection activity
against plant diseases only with each of beneficial microorganisms. The
beneficial microorganism 1 by itself showed protection activity against
tomato late blight (TLB) and tomato gray mold (TGM) whereas the
composition 3 containing the beneficial microorganism 1 showed improved
protection activity against the same diseases and additionally showed a
certain protection activity against rice blight (RCB), rice sheath blight
(RSB), wheat leaf rust (WLR) and barley powdery mildew (BPM). The
beneficial microorganism 2 by itself showed protection activity against
TLB and BPM, whereas the composition 4 containing the beneficial
microorganism 2 showed improved protection activity against TLB and BPM
and additionally showed a certain protection activity against other
diseases. The beneficial microorganism 3 by itself showed protection
activity against RCB, RSB, TGM and TLB, whereas the composition 5
containing the beneficial microorganism 3 showed improved protection
activity against RCB, RSB, TGM and TLB and additionally showed a certain
protection activity against other diseases. The beneficial microorganism
4 by itself showed protection activity against WLR and BPM, whereas the
composition 6 containing the beneficial microorganism 4 showed improved
protection activity against WLR and BPM and additionally showed a certain
protection activity against other diseases. The beneficial microorganism
5 by itself showed protection activity against TGM and RSB, whereas the
composition 7 containing the beneficial microorganism 5 showed improved
protection activity against TGM and RSB and additionally showed a certain
protection activity against other diseases. The beneficial microorganism
6 by itself showed protection activity against BPM and WLR, whereas the
composition 8 containing the beneficial microorganism 6 showed improved
protection activity against BPM and WLR and additionally showed a certain
protection activity against other diseases. The beneficial microorganism
7 by itself showed protection activity against TLB and RSB, whereas the
composition 9 containing the beneficial microorganism 7 showed improved
protection activity against TLB and RSB and additionally showed a certain
protection activity against other diseases. The beneficial microorganism
8 that has protection activity against insect larva of Plutella species
did not show any protection activity against the plant diseases, whereas
the composition 10 showed containing the beneficial microorganism 8
showed a certain protect activity similar to the composition 2 against
the plant diseases. The beneficial microorganism 9 that induces disease
resistance by itself showed protection activity against BPM and WLR,
whereas the composition 11 containing the beneficial microorganism 9
showed improved protection activity against BPM and WLR and additionally
showed a certain protection activity against other diseases. As described
above, each of the compositions of the present invention in general
showed higher control value than each of the microorganisms. The
composition 1 or composition 2 not comprising the beneficial
microorganisms also showed a certain level of increased control value.

[0068]However, considering the Example 2 that was conducted in a system
which is usually employed for the evaluation of chemical pesticides for
short periods in growth chamber that was established with stable
conditions including temperature, humidity and lighting for disease
development or insect growth, there was a certain limitation to confirm
protection activity. Thus, in order to confirm protection activity of the
compositions of the present invention against plant disease, natural
condition is considered more desirable because of plant surfaces to be
exposed to fluctuating moisture, temperature and lighting in day and
night. Plants can be also grown for longer period. Therefore, for better
confirmation of the effect of the present invention, by using adult
plants under general conditions for cultivation or similar conditions, an
experiment was further carried out repeatedly to confirm the efficacy of
the composition of the present invention.

Example 3

Protection Activity Against Cucumber Powdery Mildew and Population
Dynamics of Microbial Population

[0069]Of the compositions of the present invention, some compositions were
confirmed for their protection activity against cucumber powdery mildew
caused by Sphaerotheca fusca that naturally occur on adult plants in a
green house. Cucumber seedlings grown for 1 month after seeding were
transplanted into pots (15 cm in diameter, 20 cm in depth) that were
filled with a fertile soil (Bunong Sangto No. 5) manufactured by
Biomedia, Korea, and additionally grown until cucumber plants grew up to
the fifth or sixth leaf stages by general practice in the green house.
Then, water suspension of the compositions 1, 2, 3 and 4, the beneficial
microorganisms 1 and 2, and a chemical fungicide with active ingredient
azoxystrobin were respectively sprayed on cucumber surfaces and leaves
with 7 days of application interval for comparative studies. The
experiments were prepared by randomized complete block design with three
replications. Four cucumber plants were included for each replication.
Spray suspension comprises each composition of the present invention or
the beneficial microorganisms that are 200-fold diluted with water. Each
beneficial microorganism was prepared to have similar number of
beneficial microorganisms when diluted with the same amount of water.
Spray suspension was sufficiently applied on cucumber leaves and surfaces
by hand-held sprayer until the suspension drops off plants. Cucumber
powdery mildew was induced to occur naturally on a few cucumber plants in
the green house. In fact, the occurrence of the disease was observed when
cucumbers reached the fifth or sixth leaf stage. Protection activity was
estimated on the day of each application according to a guideline of
Rural Development Administration, Korea. Additional estimations were made
on the seventh and fourteenth days after treatment 3 (7 DAT 3 and 14 DAT
3). The protection activities against cucumber powdery mildew were given
in Table 4.

[0070]As shown in Table 4, the compositions 1 and 2 resulted in a certain
level of protection activity. The compositions 3 and 4 showed improved
protection activities when compared with each beneficial microorganism.
The chemical fungicide, azoxystrobin, did not show good protection
activity for this test. This was considered due to resistance of pathogen
to fungicide azoxystrobin.

[0071]In parallel, microbial populations on cucumber leaves were also
monitored. On the same day prior to each application using a cork borer,
three leaf discs (3 cm in diameter) were collected from the third main
leaf of cucumber plant for each treatment. The collected leaf discs were
put into 10 ml of sterile water for 30 minutes and shaken hard by hand to
prepare the leaf wash water. Microbial population was measured by 10-fold
serial dilution plating method or using LB agar medium. The beneficial
microorganisms were counted on the basis of their own unique colony forms
on the LB agar media. The result is given in Table 5.

[0072]In Table 5, microbial population density when treated with the
compositions was significantly increased when compared to the treatments
only with each beneficial microorganism. Especially, for the composition
2, population density of natural microorganisms was increased 100 times,
when compared with the non-treatment. Also microbial population of the
composition 2 was in overall higher than that of the composition 1.
Further, the composition 3 containing the beneficial microorganism 1 and
the composition 4 containing the beneficial microorganism 2 showed a
certain activity to reduce population density of natural microorganisms.
This trend indicates that the protection activities in Table 4 were due
to increased population density of each beneficial microorganism. This
experiment also confirms that population dynamics of microorganisms shown
in Table 5 was similarly reproduced with adult cucumber plants in the
green house.

Example 4

Protection Activity from Harmful Insects

[0073]Composition 10 of the present invention was tested in a laboratory
to evaluate insecticidal activity to diamondback moth (Plutella
xylostella) that harms plants belonging to Cruciferae. Cabbage seedlings
were grown in a green house, and their leaf discs (5 cm in diameter) were
sampled and soaked for 30 seconds in suspension of the composition 10
that was 2000-fold diluted. Those leaf discs were taken out and dried in
shade in a hood. Ten larvae of Plutella xylostella that had been grown up
to the third stage larvae were placed on the leaf discs and assessed for
insecticidal activity at 24, 48, 72, 96 and 120 hours after the
placement. The experiment was prepared by randomized block design with
three replications. The insecticidal activity was assessed according to a
guideline of Rural Development Administration (Korea). The result is
given in Table 6.

[0074]As shown in Table 6, the composition 10 of the present invention
resulted in 100% of insecticidal activity at 72 hour after the treatment.
The insecticidal activity was significantly higher than the case in which
the beneficial microorganism 8 was used alone. Furthermore, time to reach
100% of insecticidal activity was shorter for the composition 10 than for
the beneficial microorganism 8.

[0075]This example indicates that the compositions of the present
invention can be applied not only for the plant protection from plant
pathogens but also for the plant protection from harmful insects. In a
similar approach, the compositions of the present invention are
considered to be useful for extended use by increasing population of
beneficial microorganisms to suppress harmful organisms such as
cockroaches, ants, snails and so on.

Example 5

Herbicidal Activity

[0076]When some plant pathogens specifically infect limited number of
weedy plants, compositions of the present invention that contain these
plant pathogens can be used to suppress or control weedy plants. In this
example, tomato was taken as an example of weedy plants. The compositions
1 and 2 of the present invention that contain spores of Botrytis cinerea
at 8.00 log cfu/ml were respectively diluted at 200-fold rate and
sufficiently sprayed with 50 ml for each tomato seedling until dropping
off. Herbicidal activity was estimated with a similar method used in the
Example 2. Herbicidal activity was estimated at 3 and 7 days after
inoculation (3 DAI and 7 DAI) based on percentage of infected leaf area.
The result is given in Table 7.

[0077]As shown in Table 7, compositions of the present invention can be
used to suppress weedy plants. More specifically, the treatment of the
compositions 1 and 2 resulted in more severe occurrence of the disease to
the tomato seedlings than the treatment only with Botrytis cinerea.
However, in the case of using weed pathogens, weedy plants need to be
defined specifically and the weed pathogens need to have high selectivity
in pathogenesis. If not, weed pathogens may cause diseases to crops or
plants because weeds are also plants. Lee et al. reported a similar
result (Boyoung Lee, Dalsoo Kim, and Choong-Min Ryu. 2008. A
super-absorbent polymer combination promotes bacterial aggressiveness
uncoupled from the epiphytic population. Plant Pathology Journal
24:283-288). Inventors of the present invention showed that a composition
of the present invention can improve aggressiveness of a bacterial plant
pathogen to tomato seedlings.

INDUSTRIAL APPLICABILITY

[0078]The present invention is industrially valuable in that it provides a
composition that can supplement or replace chemical pesticides or
chemical fertilizers and the use thereof.